Patent Document 1 discloses a sand filter to filter seawater and remove a solid in the seawater.
Patent Document 2 discloses to provide water repellency to a filter medium consisting of porous particles (Particularly, in paragraph [0017]).
A solid contained in seawater may be removed with the sand filter. However, ions dissolved in seawater fail to be removed. Accordingly, the sand filter is not capable of desalinating seawater.